Compressor shaft assembly



April 18, 1950 c. sTEENsTRuP COMPRESSOR SHAFT ASSEMBLY l l I OriginalFiled June 20, 1944 I'f/l/l//l/l//l/V/f ...Eil

Inventor- CI'n-istian Steensbrup His Atto-VI e5.

Patented Apr. 18, 1950 COMPRESSOR SHAFT ASSEMBLY Christian Steenstrup,Schenectady, N. Y., assignor to General Electric Company, a corporationof New York Original application June 20, 1944, Serial No. 541,145.Divided and this application May 29, 1945, Serial No. 596,497

4 Claims. 1

My invention relates to compressors for re- 'frigerating machines andthe like and particularly to shaft assemblies for reciprocatingcompressors. This application is a division of application Serial No.541,145, filed June 20, 1944, now Patent No. 2,394,409 of February 5,1946, and assigned to the same assignee as the present application. g

In the manufacture of compressors on large scale production it isdesirable to eliminate as far as possible the rejection of parts due toeven very slight inaccuracies in alignment. It is desirable thatrelatively7 Wide tolerances be permissible for the interftting movingparts of the compressor. For example, when a reciprocating compressor isdriven by a crank it is difcult to machine accurately large numbers ofparts so that they are interchangeable and still make possible the exactalignment of the crank with respect to the cylinder. Inaccuracies inalignment of the crank and cylinder will result in binding andeventuallyin loose fits due to wear and will cause noise to be producedduring the operation of the compressor. In the assembly of areciprocating compressor, such as employed in refrigeratng machines, itis necessary to provide proper alignment of the crank shaft and cylinderand also to provide proper spacing and clearances for the crank shaftitself. Accordingly it is an object of my invention to provide acompressor for refrigeratingf machines and the like including animproved arrangement for aligning and adjusting the crank shaft thereof.

Further objects and advantages of my invention will become apparent asthe following descripton proceeds and the features of novelty whichcharacterize my invention will be pointed out with partcularity in theclaims annexed to and forming part of this specification.

For a better understanding of my invention, reference may be had to theaccompanying drawing in which Fig.v 1 is a longitudinal side elevation,partly in section, of a hermetcally sealed refrigerant compressorembodying my invention; Fig. 2 is an end view of the compressor shown'in Fig. 1 with the casing cut away and with portions of the compressorshown in section; and Fig. 3 is an enlarged view of the shaft alignmentdevice shown in Fig. 1.

Referring now to Figs. 1 and 2, I have provided a hermetically sealedmotor-driven refrigerant compressor unit I including a cylindrical shell2 having end plates 3 and 4 welded or otherwise suitably bonded theretoto form an enclosing casing. The shell 2 is constructed preferably ofsteel and constitutes the frame in which is supported a laminated corestructure 5 of an alternating current driving motor 6. 'I'he laminations5 are held in place between annular rings 'I and 8 which are welded orotherwise suitably secured to the shell 2. The motor is provided withstator windings 9 which are energized I through leads I0 passing throughsealed fittings II to the exterior of the casing. A compressor I2 isarranged within the casing I and comprises a cylinder block I3 which isrigidly secured to the ring 8 by suitable bolts or screws I4. Thecylinder block I3 is provided with a cylinder I5 in which is located apiston I6. The piston is driven by a crank shaft I'I mounted in abearing I 8in the block I3, the motor 6 being provided with a squirrelcage rotor I9 mounted on the shaft I1. The shaft II is provided withannular shoulders 20 and 2| on either side of the crank and the end ofthe vshaft remote from the motor I9 is mounted in a bearing block 22which is slidably arranged in a circular opening 23 in the cylinderblock I3. The shoulders 20 and 2I are mounted in running engagement withannular thrust bearings 24 and 25, respectively, and are retained inposition by a dished bridging member or disk 26 in cooperation with amovable camming member or adjusting plate 21. The compressor is providedwith intake and exhaust valves (not shown) which are located within acylinder head 28. Refrigerant gas which is admitted to the compressorthrough a pair of intakes 29 ows through an intake muilier 30 and thenceinto the compressor head through a conduit 3l. The gas compressed withinthe cylinder I5 by operation of the piston I6 is discharged through aconnection 32 into an exhaust muliler 33 and flows from the exhaustmuilier and out of the casing through a conduit 34 to the circuit of therefrigerating system (not shown). Vaporized refrigerant returning fromthe refrigerating system is admitted to the casing through a suctionline or return conduit 35. A body of oil or other lubricating fluid ismaintained in the casing I to a level indicated at 36, the bottom of thecasing forming a lubricant sump. Lubricant is withdrawn from the sumpthrough an intake baffle 3l by operation of a rotary oil pump 38 whichcirculates the oil to the moving parts of the compressor. This intakebaille construction is the invention of Carl H. Steenstrup and isdescribed and claimed in application Serial No. 541,143, led June 20,1944, now Patent No. 2,394,- 409 of February 5,1946, and assigned to thesame assignee as the present invention.

The motor compressor unit may be supported in any suitable manner on thestructure with which it is to be employed and has been illustrated asresiliently suspended on springs 39 and 4I).

During the assembly of the motor compressor unit, the shaft I1 is rstinserted in the bearing I8, the opening 23 in the block I3 providingroom for the passage of the shoulders 20 and 2| longitudinally intoposition. The block 22 is then placed over the right-hand end of theshaft I1 and is moved into engagement with the thrust .bearing 25, itbeing noted that the end of the shaft projects slightly beyond the endof the block 22. The dished disk 26 is then placed in position bridgingthe end of the shaft I1 and engaging the block 22. 'I'he block and diskare made approximately of the same diameter as the opening 23 so thatthey have a sliding fit in the opening and are guided by the walls ofthe opening in their axial movement, and the block pref.

erably is keyed or otherwise held against rotation in the opening. Thecamming plate 21 is then adjusted to press the bearing block 22 axiallyagainst the shoulder 2l' and also to press the shoulder 20 against thethrust bearing 24. The camming plate 21 is constructed so that thecorrect clearances between the thrust bearings and the shoulders 20 and2| may be adjusted quickly and plate 21 may then be locked in place tomaintain the adjustment.

The details of construction of the camming device 21 and the associatedparts will be apparent from the drawing'. The plate is secured to theblock I3 by suitable cap screws 4I and 42, the plate being arranged topivot on the screw 4I and being provided with a slot 43 aording lateraladjustment of the plate with respect to the shaft I1. As clearly shownin Fig. 3, the plate 21 is provided with a sloping camming surface 44which engages the outermost portion or apex of the disk 26. By looseningthe screws 4| and 42 and pivoting the plate in a clockwise directionabout the screw 4I, the camming surface 44 may be made to force the disk26 toward the left thereby to press the block 22 into engagement withthe shaft shoulder 2|. After the shaft is in position, the piston I6,together with aconnecting rod 45 and wrist pin 46, is inserted in thecylinder so that the top half of the crank bearing formed in theconnecting rod engages the crank indicated at 41. The lower half of theconnecting rod bearing indicated at 48 is then secured in place bysuitable screws 49. The compressor block is then placed in a suitablefixture vand the crank I3 turned until the piston I6 is in its outermostposition so that the crank is on dead center. The camming plate 21 isthen turned in a counterclockwise direction to force the block 22against the shoulder 2I and the screws 4I and 42 are tightened in aposition such that the shaft is locked against rotation, the

4 of the thrust bearings and shoulders, is within the requiredtolerances. The plate 21 is then locked in place by tightening of thescrews 4I and 42 to maintain the required running engagement of thethrust bearings 24 and 25 with the shoulders 20 and 2l.

It is readily apparent that the arrangement just described for adjustingthe shaft to its required position provides a simple and effective wayfor adjusting large numbers of parts in production. Further alignment ofthe connecting rod and piston is accomplished by employing theself-aligning wrist pin illustrated and which is described and claimedin the aforesaid parent application.

While I have described my invention in connection with a particular typeofv refrigerant compressor, other applications will readily be apparentto those skilled in the art. Ido not, therefore, desire my invention tobe limited to the particular construction described and illustrated andI intend by the appended claims to cover all modifications within thespirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the UnitedStates, is:

1. In a compressor or the like, a support having a shaft bearingtherein, a shaft journaled in said bearing, an annular thrust bearing onsaid support about Vsaid shaft` bearing, an annular shoulder on saidshaft arranged to engage said thrust bearing, said support having anopening therein through which said shaft may be withdrawn bylongitudinal movement, a second annular shoulder on said shaft facingtoward said 2. In a compressor or the like, a support hav-V ing a shaftbearing therein, a shaft journaled in camming plate forcing theshoulders and thrust other fixture provided with means for guagingthelongitudinal movement of the shaft I1. The plate 21 is then adjusteduntil the movement of the shaft, which is a measure of the clearancessaid bearing, an annular thrust bearing onsaid support about said shaftbearing, an annular shoulder on said shaft arranged to engage saidthrust bearing, said support having an opening therein through whichsaid shaft may be withdrawn by longitudinal movement, a second vannularshoulder on said shaft facing 'toward Isaid opening, a bearing blockslidably fitted in said 'opening and having a journal bearing engagingsaid shaft and a thrust bearing adapted to engage said second shoulder,the end of said shaft extending beyond said bearing block, a bridgingmember arranged within said opening in engagement with said bearingblock and out of engagement with the end of said shaft, camming meansfor pressing said bridging member against said bearing block foradjusting the clearances between said thrust bearings and saidshoulders, and a lock for said camming-meansA for retaining said bearingblock in position to maintain said shoulders in running engagement withsaid thrust bearings. y

3. Ina compressor or the like, a supportl havy ing a shaft bearingtherein, a shaft journaled in said bearing, an annular thrust bearing onsaid support about said shaft bearing, an annular shoulder on said shaftarranged to engage said thrust bearing, said support having an openingtherein through which said shaft may be withdrawn by longitudinalmovement, a second annular shoulder on said shaft facing toward saidopening, a bearing-block slidably fitted in said opening and having ajournal bearing engaging said shaft and a thrust bearing adapted toengage said second shoulder, the end of said shaft extending beyond saidbearing block, a dished disk arrange within said opening in engagementwith said bearing block and extending across the end ofsaid shaft out ofengagement therewith, a cam' -pivotally mounted on said support andmovable with respect to said shaft and arranged to engage said disk andpress said disk against said bearing block for adjustingr the clearancesbetween said thrust bearings and said shoulders, and means for lockingsaid cam in position on said support to maintain said shoulders inrunning engagement with said thrustbearings.

4. In a compressor or the like, a cylinder block having a main shaftbearing therein, an enlarged opening in axial alignment with saidbearing, a shaft journaled in said bearing and movable longitudinallyout of said bearing through said opening, a. crank on said shaft withinsaid opening and annular shoulders on said shaft adjacent both ends ofsaid crank, a thrust bearing on said block about said main bearing andarranged to engage the adjacent one of said shoulders, a bearing blockslidably fitted in said opening and having a journal bearing engagingsaid shaft and a thrust bearing arranged to engage the other of saidshoulders, the end of said shaft extending beyond said bearing block, adished disk arranged in engagement with said bearing block and out ofengagement with the end of said shaft, a plate -pivoted on said cylinderblock and having a sloping cam surface engaging said disk, said platebeing movable with respect to said shaft for adjusting the clearancesbetween said thrust bearings and said shoulders, and a lock forretaining said plate in position on said cylinder block.

CHRISTIAN STEENSTRUP.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,185,192 Gillespie May 30, 19162,113,691 Heller Apr. 12. 1938

